Multi-site Advanced Ranging System

Compared to classical TT&C tone ranging systems, the use of payload ranging signals has tremendous advantages for day-to-day satellite operations. The payload based ranging signal is always present and provides reliable and precise measurements without dedicated activation, and without impact on the satellite control activities. Additionally, the accuracy of payload ranging is in general superior, mainly due to the large bandwidth and high signal-to-noise ratio that it uses. This also makes payload ranging an optimal solution for orbit determination.

DARTS (Digital Advanced Ranging using Transport stream Signals)

In direct-to-home broadcasting, the DVB-S standard is used. In order to maintain the advantages of payload ranging on DVB-S operated satellites, we have developed the new DARTS. Unlike the well-known multi-lateration concept, which consists in several identical stations performing active ranging from different locations, the DARTS multi-station ranging approach is simpler. It consists of a single transmitting station, and multiple receive-only measurement stations.

The DARTS system configuration can be easily adapted to different requirements. For instance, the multi-station configuration can well be used as an orbit determination tool for a dense co-location. The DARTS system is also a cost-efficient and accurate solution. No large and costly mono-pulse tracking antenna is required. The DARTS system only requires an inexpensive and quickly deployable single ranging device added-on to the uplink path of the satellite, together with – in multi-station configuration – a few small receive-only slave stations. Even the simplest single station ranging can already considerably reduce operational efforts.